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The introduction of computer-equipped classrooms into engineering education has brought with it a host of opportunities and issues. Herein, some of the challenges and successes for creating an environment for active learning within computer-based classrooms are described. The particular teaching approach developed for undergraduate electrical engineering courses is presented. Longitudinal assessment data regarding in-class utilization of computers in the context of achieving program and course learning outcomes are shared. (Contains 1 table and 6 figures.)

This paper describes a resonant fly-back converter with thyristor switches, which can be used for the dc distribution with a PWM voltage-source inverter The proposed converter operates to change high-voltage dc into low-voltage dc with isolation and large converting ratio. The converter has a main thyristor switch and an LC resonant circuit with an auxiliary thyristor switch for commutation in the primary side of the gap transformer The operation of proposed converter was verified through computer simulations with EMTP and experiments with a hardware scaled-model. The proposed converter could be implemented with commercially available components and proven technologies for supplying electricity to the rural or remote customer Keywords: resonant fly-back converter, gap transformer, PWM (pulse width modulation), EMTP (electromagnetic transients program), TACS (transients analysis of control system)

This paper describes a static synchronous compensator using thyristor PWM current source inverter. The proposed system consists of a 3-phase thyristor bridge with commutation circuit, a dc reactor, and ac filter capacitors. The 3-phase thyristor bridge operates as a current- source PWM inverter with assistance of commutation circuit. The system operation was verified in detail through computer simulations with EMTP, and experiments with a scaled hardware model. The proposed system has two advantages of low switching loss and easy expansion of operation voltage through series connection of thyristors. Index Terms--EMTP (electro-magnetic transients program), GTO (gate turn-off thyristor), HVDC (high voltage direct current transmission), IGBT (insulated gate bipolar transistor), PAM (pulse amplitude modulation), PWM (pulse width modulation), STATCOM (STATic synchronous COMpensator), TACS (transient analysis of control systems).

The electric power acceptability curves are loci in the bus voltage-disturbance time plane. These loci separate regions of operation into "acceptable" and "unacceptable." Several power acceptability curves exist, and this paper discusses a constant energy model for the derivation of the curves. The application of the curves is discussed. The main foibles of the curves in the undervoltage disturbance region are that they do not model three-phase effects and they were not designed for rotating loads. The paper proposes a solution to these drawbacks. The use of power acceptability curves for three-phase induction motors and six-pulse rectifier loads is discussed. [ABSTRACT FROM AUTHOR]